1. Field of the Invention
The present invention relates to a Modified door for a wafer container, and more particularly to such a door, which is practical for use with a wafer transport module that requires a high sealing status.
2. Description of Related Art
Various wafer transport modules with door means have been disclosed. An example is seen in U.S. Pat. No. 5,915,562, entitled xe2x80x9cTransport Module With Latching Doorxe2x80x9d. The transport module can be made having a door on the middle, or two doors bilaterally disposed at the front side. The door comprises a rotatable cammed member having four sliding slots, and two sets of latch means respectively coupled to the sliding slots of the rotatable cammed member and vertically aligned. Each latch means comprises an elongated latch plate and an elongated lift plate. When rotating the rotatable cammed member, the latch plate and the lift plate are moved relative to each other (toward or apart from each other). The latch plate is adapted to engage into a respective latch hole on the transport module. The latch plate and the lift plate have a respective slope disposed in contact with each other. When moving the latch plate and the lift plate toward each other, the gap between the latch plate and the lift plate is relatively increased, and the door body is forced toward the inside of the transport module to seal the transport module. This door is complicated, and its manufacturing cost is high. Because the lift plate is movable, it tends to be forced out of position. Further, because the design of the rotatable cammed member and the latch means is operated to force two lateral sides of the door body against the transport module, it achieves less sealing effect.
The invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a Modified door for wafer container, which has a simple structure, and is suitable for mass production. To achieve this and other objects of the present invention, there is provided a wafer container door, comprising: a flat, rectangular door body, the door body comprising at least two peripheral sidewalls connected to one another, at least two bearing means respectively disposed at the peripheral sidewalls at an inner side, at least two guide means, a rotatable cammed member holder, at least one first slot and at least one second slot respectively extended through the peripheral sidewalls corresponding to the bearing means of the door body; a rotatable cammed member coupled to the rotatable cammed member holder, the rotatable cammed member comprising a center hub coupled to the rotatable cammed member holder, at least one coupling means each having a proximity end close to the hub, and a distal end far from the hub; at least one first link respectively coupled to the at least one coupling means of the rotatable cammed member and inserted through the at least one first slot of the door body, the at least one first link each comprising first coupling means coupled to the at least one coupling means of the rotatable cammed member, a sloped portion disposed at a bottom side thereof corresponding to the bearing means of the door body, a tongue inserted through one first slot of the door body, and second coupling means obliquely disposed at an outer side; and at least one second links respectively coupled to the at least one first link, the at least one second link each comprising coupling means respectively coupled to the second coupling means of the at least one first link, a sloped portion disposed at a bottom side thereof corresponding to the bearing means of the door body, and a tongue inserted through one second slot of the door body. Each coupling means of the rotatable cammed member can be an arched sliding slot, and the first coupling means of each first link can be a short axle coupled to one arched sliding slot of the rotatable cammed member. Alternatively, each coupling means of the rotatable cammed member can be an arched flange, and the first coupling means of each first link can be a sliding slot adapted to receive one arched flange of the rotatable cammed member. The second coupling means of each first link is an obliquely extended slot, and the coupling means of each second link is a short axle coupled to the obliquely extended slot of the corresponding first link. The bearing means can be formed integral with the door body. Alternatively, the bearing means can be separately prepared, and then coupled to the door body. The first and second links each have guide means. The door body has guide means matching with the guide means of the first and second links to guide movement of the first and second links upon rotary motion of the rotatable cammed member.